Seth Baumgartner and Jason Van Leuven open the mics for your crop steering and cultivation questions.
Office Hours Ep 73
===
[00:00:00] Kaisha: All right, what's up grommies welcome to office hours your source for free cannabis cultivation education I'm Kaisha. Welcome to episode 73. I am moderating solo today, but y'all know the drill. We are going live on youtube So if you're logging in over there, be sure to post your questions I'll also keep an eye out for questions in the chat drop them anytime And if your question gets picked we'll either have you unmute yourself or I will ask for you Also, be sure you're following us on all the platforms.
[00:00:27] Kaisha: We are on instagram and [00:00:30] social club With that let's get started jason and seth. How you guys doing today? Good. Excellent. Y'all sound ready. Let's go. Okay. Dave Wright submitted this question a few weeks ago, and he also sent a follow up. So let's start with that. He's looking for some tips for resolving or avoiding nitrogen toxicity.
[00:00:48] Kaisha: We've been dealing with some nitrogen toxicity throughout the multiple stages of growth. All of a sudden 6. 0 to 6. 2 pH, 2. 3 to 3 [00:01:00] EC happening in both HPS and LED rooms. Runoff pH was a bit high at times. Here's what he added. In addition to that, we're seeing some situation one runoff is 5. 5 ish and P two runoff is sitting is hitting 6.
[00:01:15] Kaisha: 5. Any idea why this would be happening? Input pH is 5. 8 to 6. 12. 8 to three EC HPS room. What do you guys think?
[00:01:29] Jason: Let's [00:01:30] hit the first half of that. You know, one of the things to kind of keep in mind is in that LED room, you might need to start running a little bit higher UCs just depending on how that plant's feeding.
[00:01:40] Jason: Obviously nitrogen uptake is something that's not very well regulated by the plant. I think Seth has mentioned a few episodes back. And so if we're getting low on nutrients across the board in there, It's definitely going to be getting some extra nitrogen in relationship to the other nutrients that it's pulling.
[00:01:57] Jason: One of the easiest ways to identify if you're [00:02:00] running low on EC is time series data. So looking at, Hey, as our water contents decrease you know, after our feeds, does our EC. start to rise. If it starts to drop, that means the plant is eating nutrients faster than the salts to the nutrients are concentrating in that substrate.
[00:02:21] Jason: So that might be one thing to definitely take a look at specifically for the LED room. For the HPS room, obviously, Going in at say 6. [00:02:30] 0 to 6. 2 for the pH you know, if you're a coco one gallon bags and that's exactly where you want to be. So that should be helping regulate some of the nitrogen uptake.
[00:02:40] Jason: Obviously lower pHs would make nitrogen slightly a little bit higher. Seth, what do you think for those HBS terms?
[00:02:47] Seth: Well, I mean. Big thing that keys me in is kind of the pH that you're feeding in at and then looking at what kind of media you have and possible amendments it has. If we're above a 6. 0 generally in the root zone, we're [00:03:00] going to see really unrestricted nitrogen uptake actually.
[00:03:02] Seth: That's part of why we want to be down below a 6. 0. If we look at that plant nutrient availability, we're actually able to restrict nitrogen a little bit by lowering that pH. And then as Jason said, you know, low EC conditions. So building up that osmotic pressure allows us to kind of regulate a little bit what the plant's bringing in.
[00:03:19] Seth: So if it's harder for the plant to pick up pretty much anything, then obviously nitrogen is going to be difficult too. And then you know, for your particular situation you know, we talk about it here a lot. [00:03:30] Sometimes being able to run a nutrient program that allows you to pull back on the nitrogen a little bit can be beneficial, but it's really hard to correlate a lot of these things without a root zone EC measurement.
[00:03:42] Seth: So regardless of your feed EC, we always want to see what EC we're seeing in the root zone. Just as Jason said, if our baseline's low and then it's eating everything we're putting in, that's a different situation in relation to our pH than if we have a solid baseline built up and we're actually seeing that EC rise as the water dries out and we're watching that osmotic [00:04:00] pressure build.
[00:04:00] Seth: Thank you. So, you see, PH, and then make sure you're watering adequately and resetting that nutrient balance if you have something like that going on.
[00:04:13] Kaisha: Wonderful. Thank you guys for that. And Dave Ray, good luck out there. Thanks for your patience. We were a little bit behind, we've had so many great questions, so appreciate your follow up on that. Keep us posted. All right. Mikey just posted a question here in the chat. Mikey, I'm going to read it. If you want to unmute yourself and add to it, please feel free.
[00:04:28] Kaisha: He's looking for ideal [00:04:30] flower temps for LED rooms. At what VPD and at what length of time can we cause plant stress?
[00:04:37] Jason: So for LEDs, obviously we've got a little bit lower room to room temp to radiation ratio. And basically what's going on there since LEDs are going to have less far red less of the photons are causing heat rise in the surface of those leafs.
[00:04:55] Jason: And so what usually we're looking at anywhere from 80 degrees to 84 [00:05:00] degrees for daytime temps starting off in flower. Obviously as we progress through flower, we like to start to induce a nighttime differential. It might even definitely lower your daytime temps just a little bit. Obviously that night day offset typically for the first third of the cycle and this is, you know, for a very generic strain, just start somewhere with this and the more data you can collect on the strain and how how much you need to do these temperature offsets is kind of, Kind of the best way to go about growing a strain the best, but [00:05:30] middle of the road.
[00:05:30] Jason: So first say third of the cycle you know, zero to five degree temperature differential for the second, third, usually, you know, around the five degree temperature differential. And for the last third, up to about 10 degrees night, day differential.
[00:05:45] Seth: Yeah. I mean, I think one of the challenges with switching over to led is a lot of the information out there was built out around growing under HPS is what you usually accounts for.
[00:05:54] Seth: That leaf temp offset that, you know, elevated leaf temp compared to the ambient air around it. And with [00:06:00] LEDs, we have the exact opposite. And when we're looking at LEDs, you know, there's a variety of products out in the market. And one of the easiest ways to really figure out what's going on in your room.
[00:06:09] Seth: And I mean, airflow comes into this too. We've got a lot of air flow, LEDs, not a lot of radiant heat. We typically have to run the rooms a fair bit warmer. But every grower's best bet is actually going and getting a laser thermometer, or if you're really fancy, get a FLIR camera so you can get some cool averages.
[00:06:25] Seth: But go see what your leaf temps are doing. And what we're targeting there is, you know, that [00:06:30] 0. 6 through gen, even raising that up to a 1. 0 towards the end of week three. And then, you know, going into that 1. 2 to 1. 4 range and really at the end of the day, we're targeting that leaf surface VPD we just have to work with values that we can actually easily measure every day.
[00:06:48] Seth: And as far as your question is how long, I mean, the longer you're out of a VPD range, the more your plants going to adapt to it, right? But when it adapts to that not optimal VPD range, we're not going to see as [00:07:00] good a production either. So, you know, when we look at those VPD ranges, the smaller you can keep that dead band and the narrower range, you can keep your plants in day and night.
[00:07:10] Seth: So if we're saying 0. that's day and night. We're saying 1. 2 to 1. 4. That's also day and night, so keeping it in that range both times is, you know, crucial to achieving like max transpiration, which is what we're looking for. Maximum productivity. Anytime you go outside of that dead band, that plant has to [00:07:30] adapt to the conditions outside of it, whether it's low humidity or high humidity.
[00:07:34] Seth: And what the end result is loss of production time. So, I mean, there is no minimum or maximum amount of time you can be out of VPD range. But you're potentially leaving production on the table the more time you spend out of it.
[00:07:48] Jason: Yeah, just kind of, I mean, talked about some advanced ways to know what the ideal conditions are.
[00:07:55] Jason: As Seth mentioned thermal cameras, they are my absolute favorite way to start looking at leaf [00:08:00] surface temperatures. Obviously I put some pictures up here. I've done a couple of tutorials on YouTube on how important they can be. And simply just because, you know, if I have a decent thermal camera, I can get it, you know, a few thousand samples in one picture at an instant time.
[00:08:16] Jason: I can get kind of a scan across the whole canopy as far as how much sampling I'm. Catching and, you know, in different parts of the plant, you know, you're going to see five to 10 degree temperature difference. You know, if I accidentally [00:08:30] use my laser thermometer and I hit a Cola instead of a leaf things can be way hotter than a leaf.
[00:08:34] Jason: And it's going to give me a bad reading to make adjustments off of the absolute sure way to get an idea of how you've optimized your environment is by looking at still model conductance. And so this to model conductance we're always shooting for the highest model conductance that we can get.
[00:08:50] Jason: At a given CO2 level. And if you want to, you know, make slight incremental changes into your environment, if you have the ability to take still model samples, then [00:09:00] it's going to give you an idea of whether you've improved the rate that plant can grow at or gone the wrong way. And there's always going to be thresholds, right?
[00:09:07] Jason: So if we go up too high in temperature. That plants still mates are going to start to close up a little bit. Our transpirations rates are going to go down and vice versa. If we decrease the temperature and humidity outside of the ideal range, those still mates are going to close up a little bit and we're going to just slightly less growth depending on how far out of range that we're shooting for.
[00:09:26] Jason: And you know, Seth did bring up day and night [00:09:30] VPDs you know, we're always stressing that daytime VPDs are much more important than daytime or nighttime, excuse me, VPDs. Nighttime VPDs are important cause we're trying to one, keep that plant in a stable environment to avoid susceptibility for molds and mildews.
[00:09:45] Jason: To grow but really what's happening is with without the photo period that the lights on a plant is transpiring significantly less. And so those VPD, you know, that VPD range at night is going to be much wider because it's not affecting [00:10:00] the rate of plant growth nearly as much as that VPD range during photo period on.
[00:10:07] Kaisha: Awesome. Y'all. Thank you for that answer. Mikey, great question. Thank you for posting that. All right, we're going to keep it moving. We got a lot going on YouTube. First of all, some shout outs. Poppy grows right in. Just want to say, love the chat, watched a few older vids and just helped me so much.
[00:10:21] Kaisha: with what I got going on right now. You guys are amazing. Love the show. We appreciate you, Poppy. Thank you. True exotic and clone wrote in. Love you guys. Thanks so much for all your [00:10:30] help. I've learned so much from listening on car rides. That's right. We're amazing to take on a road trip. So thank you.
[00:10:36] Kaisha: True exotic and clone. All right. Jay dropped a question here. They want to know in regards to far red supplementation towards the end of the flowering phase, how would you suggest adding the far red continuous staggered set times within 12 12, etc., also at what week in flower? What advice do you guys have for Jay?
[00:10:59] Jason: So I mean, [00:11:00] let's kind of just start off by breaking down the science of far red and how it affects the plant. So usually far red, we're looking at, you know, in the range of 700 nanometers plus it's, I think specifically it's, you know, defined as a slightly different range than that, but sure, for intensive purposes in this conversation, we're going to say, you know, 700 or 740 plus nanometers of of light wavelength.
[00:11:21] Jason: And basically what's happening is in those higher wavelengths higher frequency wavelengths that's where your chlorophyll B is reacting to the photons. And [00:11:30] so the way the plant is processing that is going to be slightly different than full spectrum. Obviously, you know, as we mentioned the other week, it's really about the levels of each of each type of light wavelength that's coming through rather than the balance of those.
[00:11:43] Jason: And so when we think about supplementing with FAR RED, really what we're doing is starting to, you know, tell that plant, Hey, let's balance you to a even more generative type of hormone. And so what that's going to be doing is giving this plant a reproductive response saying, Hey, let's make as much [00:12:00] reproductive growth as we possibly can.
[00:12:01] Jason: You know, as from the millions of years of this plant growing, it's adapted to more far reds during fall time. It's the apex angle of the sun at an apex angle.
[00:12:16] Seth: The angle that the rays are going through the atmosphere, they're going through more atmosphere.
[00:12:20] Jason: Got to go through more atmosphere. And so that those those far reds are typically going to start to be more intense towards fall. And then that plant's been adapted to knowing that in the [00:12:30] fall time, it needs to be as reproductive as possible.
[00:12:32] Jason: That's the evolution of the plant. If it can produce those, those types of plant parts before everything freezes out or it runs out of growing season. It's more likely to reproduce and evolve into that. So, when exactly is going to be definitely strain dependent?
[00:12:47] Seth: Usually when the plant starts ripening, you know, if we're looking at generally about two weeks before harvest.
[00:12:53] Seth: Is what we're looking at with most plants and there's always going to be some of those oddball genetics that aren't going to respond the same way other plants do [00:13:00] for a variety of reasons. One of the important things to remember about that also is, you know, when we're looking at plant maturity, we've got biosynthetic pathways for different cannabinoids and terpenes.
[00:13:10] Seth: So that's also another part of it's not just chlorophyll. It's not just the way the plants responding, but we're also causing degradation of different molecules that lead to a different final expression. As far as supplementing that goes, you've got a few different options. You got your classic Mitch mixed light, HPS, and then, you know, some of the newer leds have [00:13:30] far red built into them.
[00:13:31] Seth: There's also far red supplementation in the form of LED light bars. In terms of how much of your total light load you need in far red, I wish I had numbers for you. And as far as staggering it on I haven't seen any definitive evidence one way or another whether actually staggering it in and, you know, increasing amounts is going to help that much.
[00:13:51] Seth: Or if just starting to make sure you've got that range included in your light spectrum is actually going to be what gets you there. Yeah, [00:14:00] and
[00:14:00] Jason: I think a really important thing to think about here as well as pretty much any light source that you have, unless you're building your own LEDs from diodes are going to have some amount of, you know, full spectrum even LEDs are going to be containing some amount of.
[00:14:15] Jason: Far red, typically from every manufacturer that I've seen. And in order to get the best plant growth, there has to be some amount of balance in all of this. So even when we're saying, Hey, go generative stacking, or when we're going vegetative bulking, or it's still some aspects [00:14:30] that are keeping that plant balanced for the most amount of growth as possible.
[00:14:33] Jason: Obviously I guess we'll take an anecdote right now from. My experience is at my place this year is I've got some tomatoes outside and I've got some tomatoes inside and my tomatoes outside are probably as, as generative as I could grow a plant simply because I don't have my greenhouse built up yet.
[00:14:51] Jason: And they're going through nights at usually 40 degrees 40 to 45 degrees and daytime temps in the 90 to a hundred degrees. So. Obviously [00:15:00] VPD is all over the place. And then my indoor plants are at usually around 70 to 75 degrees all the time. And the plant morphology is very cool to look at next to each other.
[00:15:09] Jason: My tomatoes inside are probably six feet tall yet. I don't have nearly the bud onset and the, they're not even close to turning. red yet. Whereas outside I'm looking at plants that are two and a half feet tall and they're blowing up with fruit, but they're going to, they're going to run out of capacity to make more fruit simply because of the lack of [00:15:30] plant infrastructure.
[00:15:33] Kaisha: All right, you heard it, Jay. Good luck out there. Keep us posted on what you're doing. All right, we got one more question here. We did not plant this question. I welcome it though. Holy Nodes wants to know what crop steering software we recommend. So I guess that's an opportunity for us to talk about why AROYA is such a great crop steering.
[00:15:53] Kaisha: Software go for it.
[00:15:55] Seth: I mean, to start out with just the sensor quality, you know, if you're not getting good [00:16:00] data streaming into the software, you're trying to process it with, you're not going to get very repeatable results, you know, accuracy is one thing, precision is another. And if you don't have both, you're going to be chasing your tail one way or both ways.
[00:16:13] Seth: And that, as far as AROYA itself goes, you know, I think, Jason, you could probably speak to this. From the outset, it was designed with cannabis cultivators in mind for the cannabis cultivation process, which I think is part of what differentiates it. If you want to give some specifics.
[00:16:29] Jason: [00:16:30] Yeah, I mean, so, you know, a lot of it came from my day to day struggles as a cultivator and just how many different systems that I had to use in order to get the information I needed.
[00:16:41] Jason: So that's why we're looking at target ranges and alerts built right into the system. We're looking at things like ability to tag the chart with notes, tasks, APM events, pictures, just really attribute things more than the data because the data itself doesn't explain it. Thank you. Well, what's happening.
[00:16:59] Jason: It [00:17:00] just explains the raw output of the parameters in a room or in a root zone. And so kind of, kind of trying to equip growers with a tool set all in one interface. I was going to say the next best thing about using AROYA as a crop steering platform is the advice that you get from us is directly built off of our experience in there.
[00:17:18] Jason: Obviously you're by using AROYA, you're supporting the educational resources that that Seth and I are producing here right now. And so, you know, it's going to be directly paired with the values that we're [00:17:30] talking about. Like you said, the sensor quality allows us to have a fairly accurate calibrations built into the software and the advice that we give directly reflects those parameters.
[00:17:42] Seth: Yeah, I think one thing too is we're very agnostic when it comes to inputs. We're not tied to specific nutrient brands, light brands fan brands, name, name a product in a grow and we're not specifically tied to it. So that's another part of it. We can look we try to step back and teach people how to look at a holistic view and [00:18:00] go, okay, it's not just your sensors.
[00:18:02] Seth: It's not just your fertilizer. It's not just this. It's a holistic view. And I think that's one thing that isn't always prevalent in quite, quite a few industries, depending on who's trying to get the product out there, right? Like, our interest is in helping growers cultivate data and make better choices based on that data, not necessarily trying to sell them on any other products, not trying to tell them that any one thing is going to be the key, but more promote I'll use this [00:18:30] word carefully.
[00:18:30] Seth: sustainable growing and not in the terms of we're the most environmentally friendly, but what's a way that you can operate that's going to be streamlined, profitable and repeatable because you've quantified your operation and you have numbers and goals to hit now.
[00:18:46] Jason: It's you know, it's a balanced approach that we take as well because you know, we kind of bring experience and science.
[00:18:52] Jason: together into the recommendations that we make. It's you know, not based of information out of a laboratory and it's, you know, not based off [00:19:00] of the grow in my basement from the seventies. It's it's just based on how do we help the tens of thousands of users that we have become more successful and how do we get.
[00:19:11] Jason: More of those users as successful as they possibly can be, and that comes with training. It comes with pairing up what does agriculture biology suggest is the right way to go. What do these results show? And they don't always match up. So it takes kind of, kind of a careful mitigation of outcomes.
[00:19:28] Seth: Yeah, and I think one of the cool parts about it [00:19:30] is, you know, when you decide to invest in AROYA, you're investing in some of the same sensing technology that universities across the world, various research institutions are using to gather their own substrate, climate data soil data. So you're really getting access to data that's cutting edge.
[00:19:49] Seth: You know, in a lot of other ways, you know, if we look at a pH meters, for instance, okay, if you don't want to go spend over 2, 000 on a really nice benchtop pH meter, you're essentially buying an [00:20:00] inferior product. That's not going to give you quite as accurate and precise results, or at least not as easily.
[00:20:05] Seth: With the Roya, you're skipping kind of the subpar older tech or, you know, essentially cheaper options. And we found a way to bring you this technology at a price. So that's like pretty, pretty affordable. I feel like in terms of industry standards, when it comes to things like substrate sensing,
[00:20:22] Jason: it's, you know, it's at a price that you can really start to sample what your production looks like.
[00:20:27] Jason: You know, the, some of the products that were [00:20:30] widely available before Roya came out were in that say 1, 500 to 3, 000 per substrate sensor. And I've worked with a mini. Many of growers that ran into challenges where they just couldn't analyze the how much their drippers were clogged across the room because they had one plant with the sensor in it and, you know, 999 without sensors in them so that their ability to analyze uniformity really was not good.
[00:20:57] Kaisha: Fantastic. Thank you guys for that overview and Holy [00:21:00] Nose and anybody else out there who's interested in just learning more about what Aroya can do, head over to Aroya. io, click book a demo. One of our professionals will talk you through it. But yeah, thank you guys for that. We're going to get right back to the questions that we have here.
[00:21:14] Kaisha: We have a lot from previous weeks that we haven't even gotten to, so I'm going to just get right into it. Mike wrote in recently. Hey guys. I've loved the videos recently. I grow in Pro Mix HP and I was wondering if you have any tips on dry back in the media. I haven't found much [00:21:30] online, figured you guys might be the ones to ask.
[00:21:32] Kaisha: And feed strength in Pro Mix pretty much everything. It works great for me, but I'd love to be able to dial it in even more. Got any advice for Mike?
[00:21:40] Seth: So when we're talking about Pro Mix you know, look at what your per light ratio is in that mix. I would highly recommend doing a field capacity test and seeing where you're at compared to the volume of your substrate.
[00:21:52] Seth: And other than that, I mean, ProMix is kind of a, that was the baseline before coco really hit the market. And also the number of growers exploded [00:22:00] to the point where we're, you know, starting to become taxing on peat bogs. It's not very environmental to strip mine peat bogs to grow cannabis. So that's partially where coco came from.
[00:22:12] Seth: Otherwise peat moss and coco mixes have. Pretty much all the same soilless characteristics that we're looking for so I'll just sum it up real quick as long as you're getting a 10 to 15 percent dry back you're in a fairly healthy size media obviously pushing a little farther can be desired from time to time all the way up to a 25 percent [00:22:30] or so dry back and then otherwise you know as we've talked about before just apply your generative Transcription by CastingWords You're vegetative and your generative irrigation strategies to get through the crop.
[00:22:40] Jason: Yeah. And on top of that that field capacity test, anytime that you have questions about your media, just do some runoff tests as well. Take a look at what your what, you know, take one amount of sample and charge it just with zero zero ec and probably even a, just a basic or excuse me a neutral.
[00:22:59] Jason: PH or your [00:23:00] feed pH and do some runoff tests on that. So start collecting the very beginning of the runoff and see what it comes out as. I give you an idea of how much, well, you know, if you need to start washing that media a little bit, if you need to let it settle before you go into planting to look at that the EC of the runoff and the pH of the runoff and from manufacturer to manufacturer, it always surprises me some of the differences I see in that.
[00:23:23] Seth: Oh, absolutely. And then also, you know, be aware that like, just like the difference between rockwool and coco with [00:23:30] something like pro mix, you are going to have a small amount of cation exchange capacity. So basically that media will actually hold some of the salts that you're putting in. So if you're looking at any kind of irrigation tech or information out there, yeah.
[00:23:43] Seth: Really probably align your goals with what someone just growing in coco would do
[00:23:49] Kaisha: great tips. You guys. Thank you so much for that. Mike. Good luck out there. All right, Samuel drop the question over on YouTube. They want to know how much dry pack dry back in [00:24:00] straight can of coco 5 gallon plastic pot. So, it looks like they're looking for a little dry back range guidance.
[00:24:06] Kaisha: What do you all recommend?
[00:24:08] Jason: So, you know, in a five gallon, if it's 45% field capacity, we've got say, I'm going to just rough this out for easy math, you know, 2. 5 gallons of water available in there a big, healthy cannabis plant. And when I say big, I'm talking about as far as indoor production goes, you know, looking at a four to six and a half foot tall healthy cannabis plant.
[00:24:29] Jason: [00:24:30] Usually you're looking around, you know, three quarters of a gallon of transpiration a day. And so, as far as drybacks go you know, 0. 75 of 2. 5, what are you looking at? A quarter?
[00:24:43] Seth: Yeah, I mean, the thing to look at there is unless you've got an excessively sized plant you're not going to be able to steer it vegetatively very well at all.
[00:24:51] Seth: And that's kind of why we, you know. Not just us, but many canvas cultivators out there have settled on a smaller pot size because it actually does give us the ability to water the [00:25:00] plant every day, which helps us keep that root zone fresh, well oxygenated and avoid any root rot issues. And then the other reason is because we can go ahead and bulk it.
[00:25:10] Seth: So, if you're in a five gallon pot and you're running indoor sized plants, typically what you're going to see is you're going to run, you know, a small watering once a day, or you might be watering every other day earlier on and progressing to maybe once a day later in the run, but you're going to be growing a smaller plant for your pot size, compared to the fact that you could probably grow the same size [00:25:30] plant, a four to six and a half foot tall in a one to two gallon coco.
[00:25:33] Seth: But inadvertently you're going to be pushing shorter inter node spacing, pretty sizable nugs hopefully, and really good quality. So it depends on what your goals are. You know, that's part of why for many years a good old three to five gallon pot hand watered once a day or once or every other day brought people in their garages great results.
[00:25:54] Jason: If, you know, if you're seeing if you're seeing a daily dry back of say 5% in a five gallon pot, you've [00:26:00] probably got some pretty active plants.
[00:26:05] Kaisha: Yeah. Samuel. Thank you for the question and keep us posted. Good luck out there. All right. Going to keep it moving. We got this question on YouTube a couple of weeks back from Noise Field. They posted if runoff pH does drop below 5. 6, what's the best way to reset the pot and bring pH back up? I usually dilute feed and increase shot sizes and runoff amounts, but results vary, most of the time correcting the pH for a [00:26:30] day most of the time correcting the pH for a day or before dropping again.
[00:26:35] Kaisha: What do you guys think?
[00:26:37] Jason: So I'd look into the root of the issue because simply if, yes, you can do a correction it sounds like you're doing a correction in the right manner, but if that's not holding and you've encountered this many a times, there's something else going on there. And it's probably just coming down to a nutrient imbalance for the properties in that substrate that are causing that pH to, to drop.
[00:26:58] Jason: So if [00:27:00] you are analyzing your FEDC, we talked about that kind of in the first question today. If you have enough nutrients and you are still seeing pH swings that are significant, like you're talking about, then go get a. Leaf tissue analysis start to see, you know, what ions, what characteristics of that nutrient is the plant feeding heavier on and which ones aren't it.
[00:27:22] Jason: If you're not feeding enough nutrients in the first place, just up your nutrients. Yeah. I mean,
[00:27:27] Seth: I think that's the best place to start here. [00:27:30] A tissue analysis is going to tell you a lot. The first place I would personally start with this, you know, it sounded like you're running a diluted feed to correct your pH.
[00:27:38] Seth: An important thing to recognize with this problem is that. The plant's taking up one type of ion and leaving another. So in order to reset that balance, we need a total amount of incoming ions to not only replace the ones that have been pulled out, but also help push out the excess ones we don't want.
[00:27:54] Seth: So if you're backing off on your feed, that actual feed or, you know, for lack of a better [00:28:00] word, flush, Is it's not going to have a lasting effect on your pH change because you haven't introduced enough ions into that solution to reset the balance. So a lot of times what we're looking at is feeding, you know, sometimes higher than what you have been at, but potentially bigger feeds and trying to just push and reset that ionic balance given adequate EC levels and proper pH, we don't typically see deficiencies in a plant.
[00:28:25] Seth: So, make sure all your bases are covered and then really, like I said, look at the problem as [00:28:30] like, hey, low pH is a depletion of one type of ion in the media and we're not going to reset that. Without putting that negative charge back into it.
[00:28:44] Kaisha: Awesome, you guys. Thank you for that. Yeah, I remember a few episodes. We had a lot of PH questions, so we got a few of those left today. But yeah, appreciate that question. Alright, Daniel just posted here in the chat. Daniel, I'm going to read this and if you want to add to it. Feel free to unmute yourself.
[00:28:58] Kaisha: I feel like I have seen more and more [00:29:00] grows running what looks like a four inch rockwool cube on top of a two gallon bag of coco. Doesn't the difference in CEC and field capacity between the two cause issues? I messaged one grower who told me he does this because of faster veg and rockwool and better flour quality with coco.
[00:29:17] Kaisha: The second part of that reasoning just doesn't sit well with me. Plenty of good quality flour comes from rockwool. What do you guys think?
[00:29:24] Jason: It's actually a really pretty good option. I, you know, in ideal situations, I do like to try [00:29:30] and stick with one media type in the beginning of the plant life cycle through flower and harvest.
[00:29:35] Jason: That being said, you know, four inch rockwool cubes are very well known for their ability to be well controlled. And the veg cycle a lot of times, you know, when we have a smaller media, we can cut down the veg times and have a more vigorous plant coming out of our 18 six cycle. And on top of it, a two gallon bag, nice forgiving media for flour.
[00:29:55] Jason: We can push a two gallon down, whoo. Two gallon bag pretty hard through the flower [00:30:00] cycle. And so one of the things to think about there is yes as I mentioned, you know, staying with one type is nice Because of differences in CEC really for me, it's just the hydraulic conductivity difference between the rock wool and the coco.
[00:30:14] Jason: And the fact that we just have, you know, a single little boundary layer, typically where the plastic wrap on the rock wool ends. So at the bottom of it the thing being though, is if we do have nice exposed Explosive root growth out of that four by four by three or four by four rockwool cube.
[00:30:29] Jason: [00:30:30] It's going to penetrate our two gallon coco bag fairly quickly. Right? And so we're thinking about a running in time of usually five days, six days. And what that means is by that time, this plant is already adjusted and it's. almost its entire existence of pulling nutrients is going to be from that two gallon bag.
[00:30:47] Jason: So really, for me, the only you know, concern or challenge of having that mixed media and actually in this case, it's probably the, my favorite sizes of medias. So even better, but my, my biggest challenge there is thinking [00:31:00] about how do we make sure that rooting in process is going to be as effective as possible.
[00:31:05] Jason: And, you know, another thing to kind of think about there is Once these plants have rooted into the two gallon coco, there's not a lot of ends and hairs of those roots that are pulling water from that four by cube. It's mostly just starting to get enveloped with root crown. And so, you know, usually by say day seven we're really just thinking about that plant as being in a two gallon coco bag.
[00:31:29] Seth: Yeah. I mean, you [00:31:30] brought up an important point that I think I don't know if we've talked about much on here we could spend on it expand on it a little bit when we're talking you know most perennial plants like canter annual plants sorry like cannabis we're having root growth expand every year freshly we're not regrowing that all of that water absorption is happening you know within the last couple inches to the tip of the root.
[00:31:49] Seth: Only where the root hairs form. So to Jason's point, yes, exactly. Like all of our water absorption is actually happening primarily down in that suspended water table. That's where the highest water concentration is [00:32:00] and that's where the roots are most adapted to doing that. Basically, that is, you know, to me, I, again, I agree with Jason, I don't love mixing rockwool and coco, but it's not the worst as long as you look at what factors you have at play and the situation you're in.
[00:32:15] Seth: So part of that comes down to matching up what kind of rockwool block are you going to use versus what kind of coco. Is your coco hitting 45% VWC at field capacity or is it hitting 65? That's going to dictate what kind of, you know. What type of rockwool I might choose, I might go with something like a [00:32:30] pargrow if I'm trying to grow in really low BWC media.
[00:32:33] Seth: If I've got something higher, several companies out there right now that hit easily 60 to 70% field capacity on their straight coco. Well, fortunately that's right in the same range as what I typically see with my rockwool. Especially after I've got a plant rooted into it and then, you know, that's, that is one of the dangers, right?
[00:32:50] Seth: If we have a rockwool that will hold a lot of water and will attempt to like wick water out of the coco. Yeah. That can be overcome though with a kind of a simple physics [00:33:00] act, and that's called just setting your plant on top of the bag or on top of the block and resisting that old school urge to dig a little hole.
[00:33:09] Seth: And bury that block either all the way or partly in the soil, even or in the coco, actually even submerging that four by four by about half an inch or an inch. What it does is once the coco is around that plastic wrap, it's sealed up. No air can go under there. And basically you've got a straw now. The rock wall, once that's plastic edges sealed up, can [00:33:30] actually suck water back up.
[00:33:32] Seth: And then we don't see good routing in because we're not pushing water in the right direction through those routes, and they're not getting enough oxygen. So that is, I think, one of the biggest things is when you are mixing medias, try to match up, you know, that field capacity as best you can, because you're never going to get that matrix potential to be exactly the same.
[00:33:51] Seth: And then remember that water goes down and we want to do everything we can to keep it from going back up.[00:34:00]
[00:34:02] Kaisha: Thank you guys for that answer. That was a really good question. And yeah I'm constantly managing a very sad plant right now that I did not read in properly. You guys. So, but I'm taking notes for next year. I'll get it. All right, we got a question here. Let's see so many questions. Yes, Daniel. Thank you so much for your question.
[00:34:24] Kaisha: All right. We got a question here from Alpine agronomy. They wrote in how many plants per [00:34:30] 16 square feet. Do you suggest with a 1 gallon pot? I had better results with 2 gallon at 9 plants per 4 by 4 square than I did with a 6 with 16 1 gallon pots per 4 by 4 square. What do you guys think?
[00:34:46] Seth: Typically 9 to 12 plants, depending on pot sizes, right, where we find about the best mix of productivity, quality, because obviously the more packed in your plants are, the more your lower and inner canopy buds are going to suffer.[00:35:00]
[00:35:00] Seth: And then also there's a labor turnover, right, where if it is too inner grown and too thick it actually takes way longer to go in there and de leaf and defoliate and get any kind of plant work done. So, so what I've seen from growers going from 16 alight on most strains, if they go back to 12, a lot of times, especially if they start flipping them at, you know, really dial in that plant height, they see, you know, either equivalent or slightly increased yields just from that change alone, but also a better [00:35:30] ratio.
[00:35:30] Seth: Of that A to B NUG just because we're getting better light penetration and a more uniform and dense overall NUG structure.
[00:35:39] Jason: Yeah, really just kind of comes down to canopy density and that's some of that's going to have to do with lighting intensity, your point sources of light and type of strain, how it grows.
[00:35:53] Seth: Absolutely. And that's something to remember guys that with cannabis genetics, there's enough variation. I mean, growing under HPS, [00:36:00] I've seen strains that I can pack them in at 16 light and they do just fine. Some of them do horrible. Some strains I'll de leaf, you know, pretty hard on that lollipop.
[00:36:10] Seth: Other strains I've grown over the years. I get kind of lazy on the defoliation and luckily I still end up with some decent golf balls down in that lower canopy. So, always remember. Everything we say is this is the answer, except in some of these certain situations, so really, you know, crop registration and [00:36:30] keeping track of all your variables and then being able to analyze, like, was it the pot size or the plant density that seemed to have the bigger impact on this particular run?
[00:36:40] Seth: It's kind of the key to dissecting that for different strains over time.
[00:36:46] Kaisha: Pot size matters. Awesome. Thank you guys for that. All right. Got a question here on YouTube from John. They wrote, struggling with keeping temps down in week 5 to 6 of flower, averaging about [00:37:00] 81 during lights on and only down to 76 at night.
[00:37:03] Kaisha: Can this result in thinner buds than what's normally desired?
[00:37:10] Jason: You know, some of the things that might be able to help you is just start, you know, keep your irrigations leaned slightly more generative. If you can't do you know, some ripening aspects to that that plant and, you know, obviously start to think about what what AC capacities that, that might help you improve those environments.[00:37:30]
[00:37:30] Seth: Yeah, you know, and a part of it too is as your temperature increases, always keep your VPD in mind. So our plant response to drought is, you know, low water, which we should never hit and control the irrigation environment and also high heat and high leaf surface temp. So as your temperature goes up.
[00:37:47] Seth: We want to get that humidity up to keep that VPD in range and keep that, you know, millimeter or two around the leaf surface inside of a range where those stomata stay open and don't go into a drought response. A lot of [00:38:00] times when we see like fox tailing, for instance, a big part of it is that humidity has dropped and that immediate area on the leaf surface now is super dry.
[00:38:08] Seth: So the stomata have closed up and, you know, there's two things going on the, well, not two things. One, the eventual, the eventuality is a thinner bud structure because the plant can't keep itself cool. So it can't pack on as much material in a small area. And that's being caused by those stomata being restricted and the plant not being able to actually grow as productively.
[00:38:29] Seth: So if we have, you [00:38:30] know, classic really, Overblown weed. That's not doing very good. We will see, you know, small, sometimes really tight nugs, sometimes really loose, but if you're running high temps, make sure you're keeping up with your humidity and also maybe now, you know, where your next investment needs to be on your growth space, which is sounds like AC.
[00:38:53] Kaisha: All right, John. Let us know how that works for you. Thank you for your question. Just rounding out the hour, y'all. So if you have any questions, you're on with [00:39:00] us live. Be sure to drop it in the chat. We'll do our best to get to them. We got a question in someone wrote in rockwool. Is there any benefit in feeding a kelp based product?
[00:39:09] Kaisha: We admitted the name of this product, but they claim it will not clog drip emitters, which I find hard to believe. Any feedback would be much appreciated. Kelp based products. Y'all used anything like that. Thank
[00:39:21] Seth: you. I've played with them a little bit. Typically what we're looking at is like a little hormone booster for the plants.
[00:39:27] Seth: Is there validity to it? [00:39:30] Slight, there's some scientific evidence to show that different compounds in kelp extracts can be very good, beneficial for plant growth. If you want to implement them, I would, it says it won't cause clogged drippers. I would really look at what that looks like. Does it come out in a clear liquid with the viscosity of water?
[00:39:48] Seth: But, you know, if you're really looking at putting something like that on, maybe look at what the application instructions are and say, okay, is this something that I'm adding every day? Is it something I'm supposed to add once a week, every fifth day? What's the [00:40:00] program I'm supposed to be on? And if you really want to try it, or maybe look at hand supplementing it.
[00:40:06] Seth: Throughout the room and then, you know, log some of the morphology changes you might see in the plant, but really, when it comes to the supplements, excuse me, we want to eliminate variables as much as possible. So, you know. if that's what actually made the difference.
[00:40:21] Jason: Yeah. And the suggestion that I would have is definitely try a hand applying it first, because then if you don't see a benefit, [00:40:30] it's you know, no cost to stop using it.
[00:40:33] Jason: Whereas if you use it in your lines and it does clog your systems you're going to be out some investment. I mean, flashbacks
[00:40:40] Seth: about flashbacks to compost teas, Jason.
[00:40:45] Jason: I like hand applying compost teas.
[00:40:47] Seth: Yeah. Just don't ever let anyone broom in your ass.
[00:40:54] Kaisha: We have someone on Hangouts here that had a question, EG, did you have a question?[00:41:00]
[00:41:01] Kaisha: Not sure if they're still here, but you're welcome to type your question in the chat. We can talk about it.
[00:41:05] Guest: Can you hear me?
[00:41:06] Kaisha: Yeah, there you are.
[00:41:08] Guest: Hey there. Yeah, I just wanted to get your guys opinion about surface leaf temperature temperatures. And we're running CO2 around 1400 and got about 1000 to 1100 PAR on the...
[00:41:22] Guest: On the plants and just wanted to understand what your take was on the relationship of the environment and the surface [00:41:30] leave temperatures where they should be what the differentiation should be between those 2 temperatures.
[00:41:37] Jason: So, you know, really what's going to come down between environmental temperature and leaf surface temp is one, how much airflow is going on.
[00:41:44] Jason: You know, as these plants are transpiring, the evaporative cooling of the water vapor coming off the surface of the plant is usually going to keep them slightly lower than air temps. And that is obviously depending on how much airflow you have. So if we are reducing how much boundary [00:42:00] layer effect that the humidity and the transpiration evaporation of that water right at the leaf surface occurs, a lot of times you're going to see that a little bit less.
[00:42:08] Jason: And you actually kind of want that because it's going to be easier to manage the whole canopy. If we can start to break up some of those boundary layer environments, those micro environments around the leaf surface. And then the other was that that radiation that we talked about earlier, where some of the far reds those higher wavelengths Photons are actually, you know, increasing the surface temperature of the leaf.
[00:42:29] Seth: Yeah, and [00:42:30] I can expand on that a little bit. You know, typically early on, you know, in veg and early flower, we wanna see a leaf, an average leaf surface temp. I always wanna stress average because just like Jason said, if you take a thermometer and go take a thousand readings, you're gonna have a thousand slightly different answers.
[00:42:45] Seth: And we're looking for an average trend line that we can actually act on, but we're looking for about 80 to 80 to two degrees Fahrenheit leaf surface temp early on. Dropping that to about, you know, 75 to 78 during bulking, whatever you can kind [00:43:00] of manage, and then, you know, during bulking, we're going to start to do about a 5 degree overnight differential that will expand to a 10 degree.
[00:43:07] Seth: And, you know, this is something I've kind of, I don't think we brought up on here, but that is one of the reasons we see you know, or a lot of people will typically say they see, you know, better results in terms of color and maturation with an HPS as part of that is that leaf surface temp differential.
[00:43:21] Seth: So with an HPS, if we're running 75 degrees in the daytime and you're hitting it with that radiant heat from the light, you know, your leaf [00:43:30] surface temp might be more like 78, 79, 80. Depending on how much airflow you have and how close that leaf is to the light. Well, once the lights go off, we're, our plant's slowly moving back towards ambient room temp, and if that ambient room temp went from 75 to 65, now we've got a 15 degree differential or 12 or 13 on that HPS plant versus, you know, if we were running at 77 in the daytime and our leaf surface was 73 on that LED plant, now if we drop that [00:44:00] temp, that nighttime temp to 65 in the room, now the plant's only got a 7 degree diff or 8 degree diff, rather than a 10 to 15 degree diff.
[00:44:09] Seth: So really, you know, everything we do, and I think we've talked about this a little bit on here is really catering to that few millimeters around the leaf, that leaf surface temperature and leaf surface VPD are really what we're catering our entire environment to.
[00:44:26] Guest: Yeah, I've typically if I, when I measure my leaf [00:44:30] surface temperature, I'm I'm getting lower than my ambient temperature.
[00:44:35] Guest: And then, of course, when I get into a higher temperature, like, if I'm running 80 I'm maybe getting 76 on the leaf surface and then you know, but as I get into 82 degrees then the differential, it becomes almost nil. And, you know, at that point I start backing off. I feel like I should be backing off, but I don't know there should there be a reduction or not in the leaf temperature as opposed to the [00:45:00] ambient temperature?
[00:45:01] Jason: Typically, I see it in healthy plants and kind of what you said about when you get up to 82 in your room, I would guess that the transpiration rate of those plants is decreasing and that's why you're seeing that leaf surface temperature catch up with the ambient temperature. Thank you. So I think you're doing the right thing by backing off and not pushing quite that hard.
[00:45:22] Guest: Gotcha. Okay, great. Thanks. Thanks so much for that.
[00:45:26] Kaisha: EG, thanks for the question. I don't think we've seen you before, so nice to have you on the [00:45:30] show.
[00:45:30] Guest: Oh, right on. Thank you.
[00:45:33] Kaisha: Fantastic. Great. Yeah. Moving on to YouTube. Questions keep on coming. Tyler dropped a comment. They wrote two weeks veg, eight week flour prune.
[00:45:43] Kaisha: Week three, leaving 12 to 18 inches per cola. Defoliate five to 10 leaves covering bud sites. Week four, final defoliation strip. Week seven, sufficient plant maintenance regimen. What do you guys think? How does it sound to you? [00:46:00]
[00:46:00] Jason: To me, it sounds like it might be slightly excessive. It might be able to get away with putting just a little bit less labor into that.
[00:46:07] Jason: However, it's nice to hear it scheduled out like a good SOP. I personally probably lean on the side of the little bit lazier type of defoliation just because it's. You know, there's other ways to help manage plant growth as well that, that are a little bit less labor intensive.
[00:46:22] Jason: That being said, yeah, it's hard to argue that a proper amount of defoliation is key for the quality of bud that you're growing. [00:46:30]
[00:46:30] Seth: Yeah, you know, there's, I guess, a few different ways to go about it, like everyone says, there's a thousand ways to skin a cat to defoliate a plant. To defoliate, there's a thousand different ways you could do it.
[00:46:39] Seth: Doesn't mean they're all right, though. That's where I was going with that. But yeah, usually going Jason said typically a little more conservatively setting your plant structure early on. So sometimes when I hear that people don't do anything until week three, sometimes you can set yourself up for a little better success, especially if you've grown these same strains several times and you're used to how they, the kind of [00:47:00] structure they tend to form.
[00:47:01] Seth: You can get away with like a day one or two kind of lollipop up or right before you bring them in. And then you can save some labor on that end of stretch defoliation. Typically I like to do coming out of edge. And a week three or whenever the end of stretch is done and I'll do one more cleanup.
[00:47:17] Seth: Typically, yeah, around week seven and in there be good. You know, if you start ripping leaves too close to harvest, you're going to start encouraging mold just because you've got wounded plants going into your dry room. [00:47:30] So that's something you want to look out for. And then if you are in that case where you feel like you need to strip every single leaf from the plant to be able to dry your weed you might need to upgrade your dry room.
[00:47:41] Seth: Ideally, we want to have, you know, yeah. A healthy plant going in. And then the other thing too, always it's a balance when you're defoliating, you know, those leaves are the reason we talk about leaf surface temp and not bud temp is the leaves are what are actually transpiring and photosynthesizing. So over stripping those over stripping your plants is going to diminish the [00:48:00] yield, probably more than improper irrigation technique.
[00:48:06] Seth: Plus, of course, you kill the plant, but you can do that either way too.
[00:48:11] Kaisha: Great tips. Thank you so much, Tyler. I appreciate your post there. Thank you for sharing your data. Good luck. All right, returning back to some previously submitted questions. Hey, Ooh wrote in about pH. If you are seeing lower, if you are seeing lower of the acceptable pH range, say [00:48:30] 5.
[00:48:30] Kaisha: 4 into 5. 3, is it normal practice to increase your pH feeds to say 1, knowing that the medium will be lowering the pH soon? or would there be a different approach?
[00:48:42] Jason: This is pretty similar to what I think one of our first questions in this episode was, and that is just, you know, what are the appropriate steps for correcting a pH that's slightly off?
[00:48:52] Jason: My first question is what do our UC charts look like? You know, if we really can't make a good decision until we understand whether there's enough [00:49:00] nutrients in there to keep keep that composition, that nutrient composition balanced. Obviously if there's not enough nutrients, there's really nothing else that we can do that's going to end up in a little even really just a short term solution.
[00:49:13] Jason: Obviously you're always going to have long term issues. And obviously a really short term correction you know, modifying a pH, even if your EC is too low, it's going to be a very short term change, probably not even a solution as kind of what I was getting at there. So, you know, understanding those EC values, are they [00:49:30] high enough to sustain a balanced nutrition for that plant?
[00:49:33] Jason: You know, if you're in Brockwool, 5. 3 to 5. 4, I probably wouldn't be too aggressive at making very many changes. I would just kind of keep it in mind and continue to take pH runoff readings. If you're in coco it's probably about the time to start thinking about what might be causing that.
[00:49:49] Seth: Yeah, without those EC readings, it's really tough to say, and one, one really important thing to remember when we're looking at these pH swings as non intuitive as it seems, the bigger salt load you have if you've got [00:50:00] 10, and this is outrageous, right? Obviously, but if we had 10, 000 ppm of salt in solution and the plant took out 1500, That's much less impactful than if we had 3, 000 ppm of total salt in solution and we removed 1, 500 of it.
[00:50:14] Seth: That's going to have a much bigger effect on that, that pH in the nutrient solution than it would at a higher EC. Although it seems non intuitive to feed more and more aggressively with more nutrients, if you're at a high EC, we want to look back over time and say, [00:50:30] okay, more than likely, what are we looking at?
[00:50:32] Seth: Was it a bad input? Do we have an imbalance because of what the plant's eating? Let's say we've been stacking too much and not pushing runoff appropriately. So we've just slowly edged that pH down over time, or is it a sudden change? Is it a problem with our input? So you really want to identify So Jason said what is really causing it?
[00:50:51] Seth: And that's going to, you know, lead you to the appropriate steps to fix it. So step one, if you don't already have it, I would find a way to monitor that root zone [00:51:00] EC with something like the T12. Water content is really awesome, but the ability to see that EC in time series with a reasonable amount of accuracy is huge.
[00:51:11] Seth: And it's I guess we don't always try to sell AROYA, but we've been doing it a lot on this episode, but not a lot of sensors. I get those questions all the time. Does the, how high does the sensor read? Well, up to 30 we shouldn't see anything going above 30 in a healthy plant growing system. So you can really make a lot of good choices.
[00:51:29] Seth: Once [00:51:30] you have the numbers.
[00:51:31] Jason: Yeah. And, and, you know, I think kind of the way I like to think about it is I would rather be slightly overfeeding than slightly underfeeding. When we think about available nutrients, the plant has some ability to regulate its nutrient uptake. And so if there are you know, elements of each kind that the plant is pulling up macro and micro nutrition.
[00:51:51] Jason: Then if we have just slightly too much, that, that plant's going to regulate how much uptakes and it's going to stay balanced. Yet on the other end, if we're slightly underfeeding [00:52:00] it's going to become, it's going to become unbalanced simply because it's using up all available of certain elements.
[00:52:05] Seth: Yeah, you know, I guess a good way I like to put it is, I don't know, a decade ago when I started looking into growing in my own closet and stuff and found out about growing in a coco coir versus peat moss, which is something I was familiar with from other industries. One of the early texts I read was to mix up your nutrient solution in a five gallon bucket.
[00:52:22] Seth: If you've got one gallon pots, go dunk them until they stop bubbling, pull them up and let it drain out. And the idea was we're resetting the EC [00:52:30] in that medium to 3. 0 every day. So we're having full control. Over resetting what the pH is going to be, what the EC is going to be, and making sure that's exactly where we want it.
[00:52:40] Seth: Now that's like... That's about as low tech as you can get in monitoring and managing EC and pH inside your root zone. It's blunt force and it works, but it's also incredibly expensive and you obviously couldn't afford to just flush your entire room of plants to exactly what you want your root zone EC to be every day.
[00:52:58] Seth: Your water usage would be [00:53:00] just completely not economical.
[00:53:03] Jason: And, you know, kind of building up the The knowledge behind how to avoid this in the future is going to be one of the key things that helps you crop steer in the long run, because so many of these methods that we're using to combat an effect is a reactive type of process.
[00:53:20] Jason: And it's really hard to be crop steering when we have too many reactive treatments going on throughout a cycle.
[00:53:28] Seth: Yeah, and actually if you, [00:53:30] I'll be a salesman again, if we go back to our other question before RoyAROYAa time series data for your entire run, when you can look back, I mean, that's something I help people with pretty frequently is going, okay, you know, we've got this pH situation.
[00:53:41] Seth: How do we make a decision? Okay, you haven't been able to stack your EC above a 4. 0. And now we're in week six. So, we've been at a point where the plant's been riding on the ragged edge of having enough nutrition, and now we just hit the point in plant growth where the plant's taking out either more than we can put in, or it's taking out [00:54:00] so much that we can't really reset that ionic balance without doing some sort of incredibly massive feed.
[00:54:06] Seth: That might, you know, end up actually shocking the plant.
[00:54:11] Kaisha: Fantastic, you guys. Thank you so much for that overview. Alright, we got a comment here from Spaceship Tech. Welcome to the show, Spaceship. I don't think we've met you before. And they wrote, this is a good one, probably going to close off close out on this one.
[00:54:24] Kaisha: They wrote, when in ripening phase, my input EC is 1. 5. What are some, if any, [00:54:30] target substrate EC ranges for my final watering? What advice do you all have there?
[00:54:36] Seth: It depends on what you're, what you built up to throughout that run, you know, as a, as you're building up EC in the root zone, that plant's adapting we have the ability to change that osmotic balance, the amount of salt that's on one side of that osmotic balance anyway, really quickly by pumping too much water through there and really lowering the amount of salt or massively raising it up if we happen to feed it way too high of an EC.
[00:54:59] Seth: [00:55:00] So when you're riding out, you know, your last week's ripening, really targeting when those plants stop feeding to try to figure out when you want to taper off your EC. I mean, that's part of why we look at, you know, certain nutrient programs that'll say, Hey, run a 3. 0 all the way through. Well, part of that is because if your plan is actually ripening on its own determinant timeline, it will eventually slow down and mostly stop feeding.
[00:55:22] Seth: And at that point, most of what you're pumping into it is going down the drain. Right. But what we want to do is keep that [00:55:30] EC from either spiking up too high, you know, massively over drying it. Or dropping out. If you're at a seven baseline and you drop to zero, the plant can adapt quickly enough to continue to uptake water and nutrients and you're going to cause some root death.
[00:55:44] Seth: So I wish it was a simpler answer, but if you've been in a five to ten range, start trying to keep it in that range and maybe slowly bring it down over two weeks. But, you know, don't try to step it down more than a half a point in EC a day, typically. [00:56:00]
[00:56:00] Jason: Yeah, and just to try and put some concrete numbers, I'm just going to work off of Seth's five to 10 through vegetative bulking.
[00:56:07] Jason: If you cut that EC to one five, you're probably going to see a root zone ECs between three and 15 or two and 20, depending on how aggressive your generative steering is during ripening. Yep.
[00:56:20] Seth: And that's, you know, one thing we really try to focus on in ripening is how big is that EC swing getting?
[00:56:27] Seth: And you know, just as Jason said, we can react to it, [00:56:30] but the real value is looking at, okay, here's my buildup over time. What happens if it's too quick? What happens if it's too slow? What happens if I'm not pushing appropriate runoff? How is that affecting how I'm coming into ripening?
[00:56:45] Kaisha: Amazing. You guys.
[00:56:46] Kaisha: Thank you so much. Thank you to everybody who submitted questions. We had so many good conversations today. We really love hearing from y'all. So appreciate that. Seth and Jason rocking it as usual. Good to see you guys. Thank you for this session to producer [00:57:00] Chris. Thank you. All right. If you're looking for some Aroya gear, don't forget Aroya.
[00:57:04] Kaisha: shop is now open for business. Head over there to get you some merch. Thank you everybody for joining us for this week's episode of Arroya Office Hours. We do this every Thursday and the best way to get answers from the experts is to join us live. If you want to learn more about Arroya, book a demo at arroya.
[00:57:18] Kaisha: io. One of our experts will be happy to walk you through all the ways it can be used to improve your cultivation production process. If you have a topic you'd like us to cover on Office Hours, post questions anytime in the Arroya app. [00:57:30] Drop your questions in the chat or on our YouTube. Send us an email to sales at arroya.
[00:57:35] Kaisha: io. Note that new address. Sales. We are on all the socials. We want to hear from you. We'll send everyone in attendance a link to today's video. It'll also live on the AROYA YouTube channel. Be sure to like, subscribe and share while you're there and we'll see you at the next session. Thanks everybody.